Well – we have been implementing HTML and XML sitemaps for our client sites for a long time now. While the XML sitemap can help Google (and other search engines) help you find all important pages on your site, it is still better to ALSO have an HTML sitemap. The HTML sitemap will not only help search engines find all your pages, but actually make it easier for your site visitors, which are by far more important, to navigate through your site content and find what they are looking for quickly.
If you have a very small site, then maybe a sitemap is not needed, as long as you can get to all your pages from your main (text based) navigation, but if you have a larger site or an ecommerce site, then by all means – provide a sitemap to your visitors, so they can find what they are looking for!
A sitemap can also help you in-house to keep track of your site content – it can help you see for instance, if you should restructure certain areas and/or re-organize, because sometimes things can get a bit cluttered, especially if you add content frequently and/or add new services/subject areas to your site. Which is, by the way, a very good thing!
Anyway – here is the video from Google – enjoy!
